Overlooked Denials in Medical Billing and How to Prevent Them

Denials in medical billing can be frustrating when everything on the claim appears correct. In those cases, the problem may lie somewhere less obvious, from provider enrollment details to payer-specific requirements your team doesn’t encounter every day.

Recognizing overlooked causes of denials can help you troubleshoot faster and prevent similar issues before the next claim goes out.

Here are some less common causes of denials to check for before submitting a claim.

Commonly Overlooked Denials in Medical Billing

It’s often easier to recognize the common denials in medical billing because your team sees them regularly. You may even already have a process in place for finding them early. Less frequent causes may go unnoticed and have not yet led you to create a prevention strategy. When the claim looks correct and the usual fixes don’t work, it’s time to check other potential causes.

Rendering Provider Affiliation Mismatches

A provider can be credentialed with a payer without being properly linked to your practice’s billing entity. From your team’s perspective, the provider looks credentialed, but a claim may get denied because the payer doesn’t have the right affiliation on file.

Prevention: Work with a medical credentialing service that understands your state’s requirements. Share the diagnosis codes your practice bills and discuss special services during credentialing, particularly for Medicare, Medicaid, or VA patients. Addressing those requirements during enrollment reduces the chance of discovering a missing affiliation after claims go out.

Place-of-Service Mismatches

Place-of-service procedure codes tell the payer where care took place. A service performed in an ambulatory practice, for example, requires different place-of-service coding than one performed in a hospital outpatient department.

A mismatch can be easy to overlook because the rest of the claim may be accurate.

Prevention: Keep the current Centers for Medicare & Medicaid (CMS) place-of-service code set within easy reach during charting and coding. Your team should understand which setting applies, including the difference between office place of service (POS) 11 and hospital outpatient POS 22. 

Note that in the Azalea Ambulatory EHR, the POS field is part of the encounter record and carries through to the CPT/procedure billing and outbound claims. It inherently defaults to the practice’s location, but can be edited if needed.

Invalid Drug Information

Injectable medications have specific billing codes and additional documentation requirements. Claims involving J-codes may require National Drug Code (NDC) information as well as details about the medication administered. If the quantity administered or other required drug information is incorrect or missing, it can lead to a rejected or denied claim 

Prevention: Capture the required information when your team administers the medication rather than trying to add it later. Confirm the NDC and number of units. Then, check the dosage against the package information so the claim reflects what the patient received.

Frequency or Benefit-Limit Conflicts

Sometimes a service is appropriately documented, but the patient has reached their plan’s limit. Certain plans restrict how often a patient can receive a service, and benefit limits vary.

That makes benefit verification a potential add-on to insurance eligibility verification. Even with an automated insurance eligibility verification, some payers’ 271 responses include benefit limits while others don’t. So your team may need to confirm whether the patient has benefits remaining before providing the service. 

Prevention: Make verifying benefit limits part of your front-office workflow. Verify the number of covered visits and track usage when limits apply. If a patient needs additional care, find out whether your clinic needs to request more visits before the patient’s next appointment.

Provider Taxonomy Mismatches

One provider can have more than one taxonomy code, especially when they have more than one specialty or classification. For example, a physician could have taxonomy codes for both internal medicine and a subspecialty. 

The taxonomy you submit on a claim may need to match how the provider is enrolled with the payer for the service you’re billing. Using the wrong code can cause the payer to reject or deny a claim.

Prevention: Keep payer enrollment records current and make it clear which taxonomy code your billing team should use for which services. The claim should match the provider information the payer has on file.

CLIA Certification Issues

Laboratory billing adds another layer to monitor. Certain services require current Clinical Laboratory Improvement Amendments (CLIA) certification, and the laboratory needs the appropriate certification for the testing it performs.

Not all labs are created equal. A current certificate doesn’t necessarily mean a laboratory can perform a test.

Prevention: Track certification expiration dates and know which tests your laboratory can perform under its certification. Your billing records should reflect that same information.

Rejected vs Denied Claims: Why the Difference Matters

Some of these issues covered above may result in a rejected claim rather than a denial, which makes it important to track both. A rejected claim and a denied claim both delay payment, but the difference comes down to how far the claim gets in the process.

A rejected claim doesn’t reach the payer for review. A rejected claim fails an initial edit before adjudication, either at the clearinghouse or the payer’s front end, because information is missing or invalid. An incorrect taxonomy code, missing or incorrect J-code, or missing provider information can result in a rejection.

Missing or incorrect patient information is another common reason for a claim to be rejected. If a patient changes insurance and your practice submits an outdated member ID for them, the claim may be rejected before the payer receives it.

A denied claim reaches the payer and goes through adjudication, but the payer determines it isn’t payable as submitted. For example, the patient may not have had active coverage on the date of service, or their plan may not cover the service.

Knowing where the claim stopped gives your billing team a clearer starting point. 

• For a rejection, review the clearinghouse message and compare it with the information in your practice management software. 
• For a denial, review the payer’s reason before deciding what to correct and resubmit or whether to appeal.

Look Beyond Common Causes to Prevent Even More Denials

Some denial causes are uncommon, which makes them easy to miss before a claim goes out, especially when the claim itself seems complete and accurate. Add these less common causes to your denial-prevention strategy to improve your clean claim rate. 

Also consider tracking rejections separately from denials so your team can see where claims are stopped. Following those patterns back to the source can help you reduce claim denials instead of correcting the same issues again and again.